<!-- eslint-disable vue/no-unused-vars -->
<template>
   <!-- 商品分类导航 -->
   <div class="type-nav">
            <div class="container">
                <div  @mouseleave="leaveIndex" @mouseenter="enterShow">
                    <h2 class="all">全部商品分类</h2>
                    <!-- 只有在首页才展开,其他页面不展开 -->
                    <!-- 添加过渡动画 -->
                <transition name="sort">
                    <div class="sort" v-show="show">
                    <div class="all-sort-list2" @click="goSearch">
                        <div class="item bo" v-for="(c1,index) in categoryList " :key="c1.categoryId" :class="{cur:currentIndex == index}">
                            <h3 @mouseenter="changeIndex(index)" >
                                <!-- <a href="">{{c1.categoryName}}</a> -->
                                   <a href="javascript:;" :data-categoryName="c1.categoryName" :data-category1Id="c1.categoryId">{{c1.categoryName}}</a>
                            </h3>
                            <div class="item-list clearfix" :style="{display:currentIndex == index? 'block':'none'}">
                              
                                <div class="subitem" v-for="(c2,index) in c1.categoryChild" :key="c2.categoryId">
                                    <dl class="fore">
                                        <dt>
                                            <!-- <a href="">{{c2.categoryName}}</a> -->
                                            <a href="javascript:;" :data-categoryName="c2.categoryName" :data-category2Id="c2.categoryId">{{c2.categoryName}}</a>
                                        </dt>
                                        <dd>
                                            <em v-for="(c3,index) in c2.categoryChild" :key="c3.categoryId">
                                                <!-- <a href="">{{c3.categoryName}}</a> -->
                                                <a :data-categoryName="c3.categoryName" :data-category3Id="c3.categoryId">{{c3.categoryName}}</a>
                                            </em>
                                            
                                            
                                            
                                        </dd>
                                    </dl>
                                </div>
                            </div>
                        </div>
                      
                       
                       
                    </div>
                </div>
                </transition>
                </div>
              
                <nav class="nav">
                    <a href="###">服装城</a>
                    <a href="###">美妆馆</a>
                    <a href="###">尚品汇超市</a>
                    <a href="###">全球购</a>
                    <a href="###">闪购</a>
                    <a href="###">团购</a>
                    <a href="###">有趣</a>
                    <a href="###">秒杀</a>
                </nav>
                
            </div>
        </div>
</template>

<script>
import {mapState} from 'vuex';
//全部引入了 最好是按需引入
// import _ from 'lodash';
//按需引入
import throttle from 'lodash/throttle';
export default{
    // eslint-disable-next-line vue/multi-word-component-names
    name:'TypeNav',
    data(){
      return {
        //鼠标移入移出默认值
        currentIndex: -1,
        show:true,
      }
    },
    mounted() {
        // console.log(this.categoryList);
        //路由组件判断改变show值
        if(this.$route.path !== '/home'){
            this.show = false;
        }
    },
    computed:{
        ...mapState({
            //对于数组写和对象写法,建议写对象写法,毕竟不是一个数据,数据多了数组写法会显得臃肿
            categoryList:state => state.home.categoryList
                
             
        })
    },
    methods: {
        //鼠标进入修改currentIndex
        //使用对象形式写 做节流处理 throttle不要使用箭头函数,上下文this保持一致
        changeIndex: throttle(function(index){
            this.currentIndex = index;
        },50),
        //鼠标移出恢复原值
        leaveIndex(){
            this.currentIndex = -1;
            if(this.$route.path !== '/home'){
                this.show = false;
            }
        },
        
        //路由跳转的方法
        goSearch(e){
            //实现: 路由跳转和路由传参,那么多跳转不肯能都写声明式导航 或者编程式导航
            //解决方案: 事件委托+编程式导航
            //问题: 谁点击了,怎么拿到这个触发事件对象目标 解决: e.target
            //问题: 点击a标签才会跳转,那么怎么确定是否点击的是a标签  解决: 自定义属性,data-categoryName
            //问题: 确认了点击的是a,怎么区分不同级别的呢? 解决: 自定义属性动态数据绑定categoryName
            //拿到触发事件目标
            let element = e.target;
            //获取到带有data-categoryName的节点
            //节点有一个属性dataset 可以获取到节点的自定义属性和属性值
            console.log(element.dataset);
            let {categoryname,category1id,category2id,category3id} = element.dataset;
            //带有category值一定是a标签l
            if(categoryname){   
                //区分不同级别 还是自定义属性 使用id
                //做一些简单处理 方便跳转以及传参
                let location= {name:"search"};
                let query = {categoryName:categoryname}

                //级别判断
                if(category1id){
                   query.category1Id = category1id;
                }else if(category2id){
                    query.category2Id = category2id;
                }else{
                    query.category3Id = category3id;
                }
                //做判断,如果params有参数(搜索框里面用户输入内容)
                if(this.$route.params){  //??? 判断了个寂寞,空对象转布尔值永远是true
                    location.params = this.$route.params;
                   //整理参数
                   location.query = query;
                }
               
                //路由跳转
                this.$router.push(location);
            }
        },
        //当鼠标移入展开show
        enterShow(){
             this.show = true;
        }
    },
}

</script>

<style lang='less' scoped>
  .type-nav {
        border-bottom: 2px solid #e1251b;

        .container {
            width: 1200px;
            margin: 0 auto;
            display: flex;
            position: relative;

            .all {
                width: 210px;
                height: 45px;
                background-color: #e1251b;
                line-height: 45px;
                text-align: center;
                color: #fff;
                font-size: 14px;
                font-weight: bold;
            }

            .nav {
                a {
                    height: 45px;
                    margin: 0 22px;
                    line-height: 45px;
                    font-size: 16px;
                    color: #333;
                }
            }

            .sort {
               
                position: absolute;
                left: 0;
                top: 45px;
                width: 210px; 
                height: 471px;
                position: absolute;
                background: #fafafa;
                z-index: 999;

                .all-sort-list2 {
                    .item {
                        h3 {
                            line-height: 30px;
                            font-size: 14px;
                            font-weight: 400;
                            overflow: hidden;
                            padding: 0 20px;
                            margin: 0;

                            a {
                                color: #333;
                            }
                        }

                        .item-list {
                            display: none;
                            position: absolute;
                            width: 734px;
                            min-height: 460px;
                            background: #f7f7f7;
                            left: 210px;
                            border: 1px solid #ddd;
                            top: 0;
                            z-index: 9999 !important;

                            .subitem {
                                float: left;
                                width: 650px;
                                padding: 0 4px 0 8px;

                                dl {
                                    border-top: 1px solid #eee;
                                    padding: 6px 0;
                                    overflow: hidden;
                                    zoom: 1;

                                    &.fore {
                                        border-top: 0;
                                    }

                                    dt {
                                        float: left;
                                        width: 54px;
                                        line-height: 22px;
                                        text-align: right;
                                        padding: 3px 6px 0 0;
                                        font-weight: 700;
                                    }

                                    dd {
                                        float: left;
                                        width: 415px;
                                        padding: 3px 0 0;
                                        overflow: hidden;

                                        em {
                                            float: left;
                                            height: 14px;
                                            line-height: 14px;
                                            padding: 0 8px;
                                            margin-top: 5px;
                                            border-left: 1px solid #ccc;
                                        }
                                    }
                                }
                            }
                        }

                       
                    }
                    .cur {
                        background-color: orange;
                        h3 {
                       
                            a {
                                color: white;
                            }
                        }
                        
                    }
                }
            }
            //过渡动画的样式
            //过渡开始状态(进入)
            .sort-enter{
                height: 0px;
            }
            //过渡动画结束状态(进入)
            .sort-enter-to{
                height: 471px;
            }
            //定义动画时间,速率
            .sort-enter-active{
                transition: all .3s linear;
                overflow: hidden;
            }

        }
    }
</style>
